Been shooting an "old" version contender in 44 Magnum - fantastic with red dot sight! Opportunity knocked to purchase .357 mag barrel as well as .22 lr barrel for $125 each - previous owner has old style contender also with cougar engraving. went to the range shot several .44's no issues. Changed out the .22 LR barrel - click no bang.. oh yeah turn the little button in the hammer for rim fire...click no bang again & nearly impossible to open. head scratching, muttering & lots of looking realized the hammer block wasn't moving out of the way. pulled the pivot pin - only way to open up this time & tried the .357 barrel - same crap click no bang - hammer block stopping primer strikes!!! Home total disassembly , clean & lube , search for the little spring that went flying ,etc. THEN checked the new barrels for function without the trigger assy. barrel doesn't trip the little rocker that allows the hammer block to move! Close inspection reveals "new" barrels have a square end on the barrel lock whereas the .44 barrel has a tapered or beveled end. What have I got myself into??? Any options as I understand T/C has been bought out by S&W and customer service on T/C has been so-so at best...